The Kerr solution to Einstein's field equation describes these entities which are rotating and the Reissner-Nordstom solution to Einstein's field equations describes one of these with a charge. The no-hair theorem states that the only externally observable parameters that can characterize these are: charge, mass and angular momentum. It has been posited that a supermassive variety of these could lie in the center of galaxies. For 10 points, name 
The Kerr solution to Einstein's field equation describes these entities which are rotating and the Reissner-Nordstom solution to Einstein's field equations describes one of these with a charge. The no-hair theorem states that the only externally observable parameters that can characterize these are: charge, mass and angular momentum. It has been posited that a supermassive variety of these could lie in the center of galaxies. For 10 points, name these entities which don't allow anything, even light, to escape when it crosses their event horizon.
The Kerr solution to Einstein's field equation describes these entities which are rotating and the Reissner-Nordstom solution to Einstein's field equations describes one of these with a charge.
{black hole}